| Messier 14 | |
|---|---|
Messier 14, from 2MASS |
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| Observation data (J2000 epoch) | |
| Class | VIII |
| Constellation | Ophiuchus |
| Right ascension | 17h 37m 36.15s[1] |
| Declination | -03° 14′ 45.3″[1] |
| Distance | 30.3 kly (9.3 kpc) |
| Apparent magnitude (V) | +8.32[1] |
| Apparent dimensions (V) | 11.0′ |
| Physical characteristics | |
| Radius | 50 ly[2] |
| Other designations | NGC 6402[1] |
| See also: Globular cluster, List of globular clusters | |
Messier 14 (also known as M14 or NGC 6402) is a globular cluster in the constellation Ophiuchus. It was discovered by Charles Messier in 1764.
At a distance of about 30,000 light-years, M14 contains several hundreds of thousands of stars. At an apparent magnitude +7.6 it can be easily observed with binoculars. Medium-sized telescopes will show some hint of the individual stars of which the brightest is of magnitude +14.
The total luminosity of M14 is in the order of 400,000 times that of the Sun corresponding to an absolute magnitude of -9.12. The shape of the cluster is decidedly elongated. M14 is about 100 light-years across.
A respectable total of 70 variable stars is known in M14, many of the W Virginis variety common in globular clusters. In 1938, a nova appeared although this was not discovered until photographic plates from that time were studied in 1964. It is estimated that the nova reached a maximum brightness of magnitude +9.2, over five times brighter than the brightest 'normal' star in the cluster.
Slightly over 3° southwest of M14 lies the faint globular cluster NGC 6366.
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